Tape labels are identifiers given to volumes of
magnetic tape
Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magne ...
.
There are two kinds of tape labels. The first is a label applied to the exterior of tape cartridge or reel. The second is data recorded on the tape itself.
Visual labels
Visual labels are human readable.
The labels have evolved to have
barcode
A barcode or bar code is a method of representing data in a visual, machine-readable form. Initially, barcodes represented data by varying the widths, spacings and sizes of parallel lines. These barcodes, now commonly referred to as linear or o ...
s that can be read by
tape libraries
In computer storage, a tape library, sometimes called a tape silo, tape robot or tape jukebox, is a storage device that contains one or more tape drives, a number of slots to hold tape cartridges, a barcode reader to identify tape cartridges a ...
. Reading the barcode label is often much faster than mounting the tape volume and reading the identification information written on the media. To read the bar code, the tape library need only position the volume in front of the bar code reader.
Magnetic labels
Originally, 7- and 9-track
data tapes only had human readable labels on them (i.e. as far as the operating system was concerned they were unlabeled). Somebody wishing to use a particular tape would ask the operator to mount that tape; the operator would look at the human readable label, mount it on a
tape drive
A tape drive is a data storage device that reads and writes data on a magnetic tape. Magnetic tape data storage is typically used for offline, archival data storage. Tape media generally has a favorable unit cost and a long archival stability.
...
, and then tell the operating system which drive contained the tape of interest. That had some drawbacks: the operator might mount the wrong tape by mistake, or he might type in the wrong identification.
A solution was to record some tape identification information on the tape itself in a standard format. This
metadata
Metadata is "data that provides information about other data", but not the content of the data, such as the text of a message or the image itself. There are many distinct types of metadata, including:
* Descriptive metadata – the descriptive ...
allowed the operating system to quickly recognize a volume and assign it to the program that wanted to use it. The operating system would notice that a tape drive came online, so it would try to read the first block of information on the tape. If that was a
volume label
In computer data storage, a volume or logical drive is a single accessible storage area with a single file system, typically (though not necessarily) resident on a single partition of a hard disk. Although a volume might be different from a physic ...
, then the operating system could determine what to do with it.
Some computer systems used similar labels on other serial media, for example
punched card
A punched card (also punch card or punched-card) is a piece of stiff paper that holds digital data represented by the presence or absence of holes in predefined positions. Punched cards were once common in data processing applications or to di ...
decks and sometimes line printer output.
IBM tape labels
IBM tape labels with VOL/HDR/EOV/EOF records. IBM tape labels on 9-track tapes use
EBCDIC
Extended Binary Coded Decimal Interchange Code (EBCDIC; ) is an eight-bit character encoding used mainly on IBM mainframe and IBM midrange computer operating systems. It descended from the code used with punched cards and the corresponding six- ...
character encoding; 7-track tapes (now obsolete) used
BCD encoding.
ANSI tape labels
ANSI/ISO/ECMA tape labels are similar to IBM tape labels but use the
ASCII
ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because of ...
character set on 9-track tape. When originally defined in the mid-1960s, they used BCD on 7-track tape.
Burroughs tape labels
The
Burroughs MCP
The MCP (Master Control Program) is the operating system of the Burroughs small, medium and large systems, including the Unisys Clearpath/MCP systems.
MCP was originally written in 1961 in ESPOL (Executive Systems Problem Oriented Language). In ...
running on the
B5000
The Burroughs Large Systems Group produced a family of large 48-bit mainframes using stack machine instruction sets with dense syllables.E.g., 12-bit syllables for B5000, 8-bit syllables for B6500 The first machine in the family was the B5000 in ...
was one of the earliest systems to automatically read tape labels. When designed in 1961 it used a proprietary format coded in BCD (strictly,
Burroughs Interchange Code or BIC), but was later able to read standard 7-track ANSI (then styled USASI) labels.
RFID tags
Some tapes (e.g., later versions of
Linear Tape-Open
Linearity is the property of a mathematical relationship (''function
Function or functionality may refer to:
Computing
* Function key, a type of key on computer keyboards
* Function model, a structured representation of processes in a syste ...
and
Advanced Intelligent Tape
Advanced Intelligent Tape (AIT) is a discontinued high-speed, high-capacity magnetic tape data storage format developed and controlled by Sony. It competed mainly against the DLT, LTO, DAT/DDS, and VXA formats. AIT uses a cassette similar to ...
) are using
RFID
Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. An RFID system consists of a tiny radio transponder, a radio receiver and transmitter. When triggered by an electromag ...
tags. Often these RFID tags include tape metadata such as data locations, number of tape errors encountered, number of times the entire tape was read or written, etc.
[ ]
See also
*
Microsoft Tape Format Microsoft Tape Format (MTF) is the tape format used by several backup tools for the Microsoft Windows platform. Notable examples include Microsoft's NTBackup program, Backup Exec and the backup utilities included in Microsoft SQL Server.
Several ...
References
External links
ECMA-13, File Structure and Labelling of Magnetic Tapes for Information Interchange, 4th ed, December 1985.* http://publib.boulder.ibm.com/infocenter/iseries/v5r4/index.jsp?topic=/rzatb/vdefn.htm
* http://techpubs.sgi.com/library/tpl/cgi-bin/getdoc.cgi?coll=linux&db=bks&fname=/SGI_EndUser/TMF_UG/ch02.html
* https://it-dep-fio-ds.web.cern.ch/it-dep-fio-ds/Documentation/tapedrive/labels.html
{{DEFAULTSORT:Tape Label
Computer storage tape media